Nanostructure

Nanostructure refers to the arrangement of matter at dimensions on the order of nanometers within a larger material, where nanoscale features influence properties. Common manifestations include nanoparticles, nanorods, nanotubes, nanowires, nanosheets, and porous nanoscale architectures. Nanostructures are characterized by features typically below 100 nanometers, although some definitions extend into the low hundreds of nanometers. The small size leads to high surface area to volume ratios and, in many cases, quantum size effects, both of which can alter optical, electrical, magnetic, and mechanical behavior.

Design and synthesis can follow bottom-up approaches—chemical synthesis, self-assembly, and templating—or top-down methods such as lithography and etching. Achieving precise control over size, shape, composition, and interfaces is central to tuning properties.

Applications span electronics (quantum dots, nanowire devices), energy (battery electrodes, catalysts, and supercapacitors), sensing, photonics, coatings, and biomedicine (drug delivery, imaging). Nanostructured materials are also used to improve the strength, durability, or functionality of composites.

Characterization relies on microscopy (transmission and scanning electron microscopy, atomic force microscopy), spectroscopy, X-ray scattering, and surface analysis to determine size, morphology, crystallinity, and composition.

Safety and environment considerations address potential toxicity, environmental fate, and lifecycle impacts, prompting responsible development and regulation as nanostructures move toward commercial use.

Historically, interest in nanoscale structures grew with the rise of nanotechnology in the late 20th century, with rapid advances in fabrication and imaging enabling both fundamental study and practical applications.